In recent years, there has been proposed a tactile presentation device that transmits vibrations to a user when the user touches a key on a touch panel type keyboard or the like, so as to give the user tactile feedback and makes the user feel that the key has been “pressed”.
For example, Patent Document 1 proposes a tactile presentation device including a diaphragm and a piezoelectric film. The piezoelectric film is connected in a state where stress is generated in the diaphragm. The piezoelectric film is an example of a film that expands and contracts in a planar direction by application of a voltage. When the piezoelectric film expands and contracts, the diaphragm vibrates in a normal direction.    Patent Document 1: International Publication No. 2015/053247